Carbureter



w. E. DEWEY.

CARBURETER.

APPLICATION FILED JAN. 17. 1917.

1,3 4,799. Patented July 19,1921.

Arm/v56 PATENT OFFICE.

WILL E. DEWEY, OF ROCKFORD, ILLINOIS.

CARBURETER.

Specification of Letters Patent.

Patented July 19, 1921.

Application filed January 17, 1917. Serial No. 142,820.

ToaZZ 'w hom it may concern Be it known that I, WILL E. DEWEY, a citizenof the United States, residing at Rockford, in the county of lVinnebagoand State of Illinois, have invented certain new and useful Improvementsin Carbureters, of which the following is a specification.

This invention relates in general to fuel mixing devices, and has moreparticular reference to carbureters especially adapted for use withinternal combustion engines.

It is well recognized that inefficiency and poor operation of internalcombustion engines caused by improper fuel mixture is due mainly tofaulty carbureter design. In the carbureter liquid fuel is volatilizedby the admixture in various ways of air, the fuel being most readilyignitible and effective when most completely volatilized with the properamount of air; and it follows that such designs as cause stratificationand con densation of the fuel in the carbureter are inimical toeconomical and efficient operation.

The primary object, therefore, of my invention is to overcome theobjectionable features of carbureters now in use and to obtain acarbureter of high efficiency by providing for the mixture of fuel andair in a novel manner that will insure thorough volatilization of thefuel with the proper amounts of air underall conditions of operation andwill avoid stratification and the general consequences of condensationof the fuel.

Another important object of my invention is to provide a carbureter inwhich the supply of secondary or auxiliary air is automatically governedin a novel manner to completely volatilize the fuel and carry it in suchcondition to the engine.

In furtherance of these general objects I have provided a carbureter ofgenerally improved construction so far as relates to the parts formixing and conducting the fuel and air and controlling the supply ofauxiliary air. A most important feature in this connection is the novelarrangement of the fuel and air conduits and the intake of the secondaryor auxiliary, all of which will be fully described hereinafter. Anotherfeature is the provision of a diffusing or distributing plate, which inconjunction with the secondary air intake, causes the primary mixture tobe more fully volatilized and supplied with the proper amount of air.

A still further object of the invention is to provide an improved meansfor automatically controlling the supply of secondary air and also forvarying such supply by means of an adjustment under control of theoperator so that the best results may be obtalned under variousconditions of operation.

Other objects and many of the inherent advantages of my invention willbe readily appreciated by those skilled in the art as the same becomesbetter understood by reference to the following description whenconsidered in connection with the accompanying drawings, wherein Figure1 is a vertical sectional view through a carbureter embodying myimprovements; and

Fig. 2 is a horizontal sectional view taken on the line 2-2 of Fig. 1:

Since my improvements have no special reference to the means forsupplying and controlling the supply of liquid fuel, or to the throttlecontrolled outlet from the carbureter, or to the arrangement of thisoutlet, I have illustrated these in a somewhat conventional and briefmanner. The fuel supply may be of any suitable or preferred form, and inthis instance I have shown a well known form of nozzle or jet 4,communicating through passages 5 with a float chamber 6 in which theproper level of the liquid fuel supplied through the pipe 7 ismaintained by a float 8 in a manner not shown but well understood in theart and forming no part of the present invention. The nozzle 1 ispositioned centrally within a primary air intake casing 9 which passesthrough an aperture in the bottom of the float chamber casing and isinteriorly threaded to receive the threaded extension 11 of the mainbody of the darbureter. thereby securing the float chamber housingrigidly to the main carbureter body. This body is shaped to provide acomparatively long and narrow primary air tube or conduit 12 into thelower or inlet end of which the nozzle at projects. The upper or outletend of the primary air conduit is widened and opens into a mixingchamber 13 more fully described hereinafter, which chamber is in realitythe top end of a secondary conduit 14 surrounding the primary conduit 12and having an outlet 15 which connects with the engine manifold 16 andis equipped with a throttle valve, such for instance as an ordinarybutterfly valve 17, adapted to be controlled by an operator. The termsprimary conduit and secondary conduit refer .to the general conduitthrough which the fuel passes and distinguishes different portions ofsaid general conduit by the air supplies. That is, the conduit throughwhich passes the fuel laden with the primary .air is termed the primaryconduit, and from the point the secondary or auxiliary air is added theconduit is spoken of generally as the secondary conduit. Fuel is drawnfrom the nozzle 4 by the engine suction and will pass upwardly throughthe primary conduit 12 into the mixing chamber 13 and will be drawnaround the top end of said conduit and down through the secondaryconduit to the outlet 15 and thence to the engine, as indicated by thearrows in Fig. 1. As the liquid is drawn from the nozzle 41-, theprimary air drawn upwardly through the conduit 9 will be deflected tothe center of the channel by the converging wall 18 so that the velocityof the air is considerably increased and the air in thus mixing with thefuel will atomize and vaporize the same. This primary mixture willbe-drawn upwardly through the long narrow conduit 12, which whileholding the mixture in a confined area allows it to become quitethoroughly volatilized before it is supplied with secondary of auxiliaryair. In order to better vaporize the mixture during its passage throughthe primary conduit the latter is slightly tapered longitudinally, asshown in Fig. 1.

By means of an annular projection or diffusing plate at the outlet endof the primary conduit in conjunction with the arrangement of'theadjacent parts a conduit is formed, causing the mixture upon leaving theoutlet end of the primary conduit to be distributed and'diffusedradially and to pass outwardly in all directions and thence down aroundthe peripheral edge of the plate. The conduits are so relativelyproportioned as to give confined areas or passages in which it isdesired to positively control the mixture and hold it, as it were, inpositively defined channels, so that the secondary air may be properlymixed with the fuel in a manner that will insure thorough volatilizationand will preclude stratification. The diffusing plate 19 provides anupwardly and outwardly flaring annular wall, the diameter of which isslightly greater than that of the secondary conduit 14. The passage fromthe outlet end of the primary conduit around the peripheral edge of thediffusing plate and into the secondary conduit is restricted and definedby the inner walls of the mixing 1 chamber casing 13 and also by asecondary and directly opposite the outlet of the primary conduit. Thisvalve is secured to a stem 22 slidably mounted in a sleeve 23 in turnlongitudinally slidable in the central spider bearing 24- of a valveseat member. 25 threaded into the top of the casing 13. Spring means areprovided for-yieldingly resisting movement of the valve in an openingdirection and consists of a relatively light expansion spring26'interposed between the flange 27 of the collar'23 and a nut 28adjustable on the upper end of the valve stem and a second expansionspring 29, preferably of greater strength than the spring 26, coiled onthe valve stem and interposed between the upper end of the collar 23 andthe lower end of the nut member 28, although terminating short of thenut member so as not to be normally effective. The collar 23 may beremoved longitudinally upon and with respect to the valve 7 stem to'compress thev spring 26 and also to bring the spring 29 into operation,so that the yielding resistance to the opening move ment of the valvemay be varied at the will of the operator. A. suitable lever under thecontrol of the operator is provided for de-' termining the positionofthe collar 23 to regulate the supply ofsecondary air under differentconditions of operation. This lever may be in the form of a bell crank31 pivoted at 32 on one of the spider arms of the valve seat member andshaped so that the end of the bell crank is bifurcated and extendsbeneath the annular flange 27 of the collar 23. Any suitable connectionmay be attached to the end 34 of the bell crank lever for the purpose ofrocking the same and holding it in any of a plurality of adjustedpositions. When the lever is rocked in a clockwise direction itsbifurcated end 33 will slide the collar 23 upwardly on the valve stem,thereby compressing first the spring 26 then the spring 29, the stop 35on the lever limiting its movement by contact with the valve seatmember. A. cap 36 may be mounted on the collar 23 to protect the springsand also to prevent tampering withthe adjusting nut 28, since it isintendedto properly adjust the nut when the carbureter is manufacturedand to adjust the spring pressure only by means of the lever 31 or anysuitable means for moving the collar 23 lengthwise. It will be notedthat the valve 21 is not seated, but is suspended in a balancedposition.- And since the spring 26 is thus preferably adj usted so asnot to seat the valve under certain operation, the valve will be furtheropened by the suction of the engine, allowing a very plentiful supply ofsecondary air to be drawn in. This supply may bedecrea sed and varied atwill by adjustment of the lever 31 and when the same is adjusted to theY fullest extent so that the combined pressures iao of the springs 26and 29 hold the valves seated, the admission of secondary air is shutoff so that the valve serves as a choker.

Assuming that the carbureter is attached to an automobile and operatedat ordinary speeds, for instance up to approximately 20 miles an hour,the valve may be set to operate in the manner shown in Fig. 1. Thismeans that a plentiful amount of secondary air will be supplied to thefuel and by causing this air to thoroughly disintegrate and atomize thefuel, producing a fully vaporized mixture, a very effective explosivefuel will be obtained, enabling very economical consumption due to therelatively large proportion of air. During this operation the fuel drawnupwardly through the primary conduit 12 is equally distributedcircumferentially about the plate 19 due to the even suction created bythe arrangement of the secondary conduit. The fuel upon thus leaving theconduit 12 literally hugs the top wall of the diffusing plate 19 byreason of the fact that the valve 21 is drawn down so as to somewhatrestrict the passage and also cause-the channel of the suction to turnsharply about the peripheral edge of the plate 19, making asubstantially complete turn, in the reverse direction. The influence ofthe incoming secondary air also tends to hold the fuel toward the plate19 so that in being drawn over and around this plate it is diffused andfinely separated and atomized. Thus, when the fuel leaves the peripheraledge of the plate 19 and is drawn at a high velocity into the restrictedperipheral channel of the mixing chamber and enveloped in the secondaryair, the fuel will be further and more fully volatized and carried inthis condition to the engine. It will be noted that stratification ofthe fuel and secondary air is practically impossible, since the fuelwhich has been considerably vaporized in its passage through therelatively long narrow primary conduit and is further divided anddiffused by its distribution and passage over the plate 19 enters acircumferential body of secondary air at a high velocity and in a mannervery favorable to producing a fully volatized fuel. During thisoperation the valve may be said to have an automatic balancing effect,since when the speed is increased by operation of the valve 17 toincrease the suction the valve will be opened to a greater extent. Theincreased suction will draw the fuel from th primary conduit at agreater velocity, so that the tendency of the fuel will be to passupwardly and over and out of contact with the diffusing plate. However,the valve in being drawn down to a greater extent proportionatelyrestricts the outlet passage from the conduit 12 thereby causing thefuel to be diffused and expanded by the influence most favorable forproper admixture therewith. hen the speed is further increased, thespring pressure on the valve may be increased by adjustment of the lever31, it being evident that as the spring pressure is increased the supplyof secondary airwill be decreased in proportion to the gasolene orkerosene drawn from the nozzle. 'WVhen starting an engine, especially incold Weather, the lever 31 would be adjusted so as to serve as a chokerto practically prevent the admission of secondary air and thus allow afull rich mixture to be drawn to the engine.

While I have shown and described one practical embodiment of myimprovements, it should be understood that various changes in theconstruction and modifications in the design may be made withoutdeparting from the spirit and scope of the invention as expressed in theappended claims.

I claim:

1. In a carbureter, the combination of a primary mixture tube, asecondary mixing chamber having an air inlet port and a mixture outlet,an inwardly opening disk valve for said port, said tube extending intosaid mixing chamber through the mixture outlet end. thereof, a fuelnozzle in said tube, and a distributing disk within the mixing chamberat the discharge end of the primary mixture tube, co-axial with the diskvalve and positioned between the valve and mixture outlet, whereby theprimary mixture will be. radially distributed by said plate and will bedrawn into a peripheral body of secondary air in the mixing chamher andthence through the mixture outlet in the opposite direction from that inthe primary mixture tube.

2. In a carbureter, the combination of a vertical primary mixture tube,a fuel nozzle at the lower portion of said tube, a distributing disk atthe upper or discharge end of the tube, a mixing chamber surrounding thedistributing disk and having an air inlet port above the disk and amixture outlet below and co-axial with the disk, whereby to cause theprimary mixture drawn upwardly through the primary tube to passoutwardly over the distributing disk into the mixing chamber and aroundthe peripheral edge of said disk and thence downwardly through themixture outlet, and an inwardly opening valve for said air inlet portfor admitting secondary air to the mixing chamber.

3. In a carbureter, the combination of a primary mixture tubeterminating at its discharge end in an annular distributing disk, theface of which is dished toward the mouth of the primary tube, a mixingchamber surrounding the distributing disk and drawn around theperipheral edge thereand having an air inlet opening at the face of intothe mixing chamber and into a peside of said disk and a mixture outletat ripheralbody'ofsecondary air, and thence 10 the opposite sidethereof, and an inwardly in a reverse direction through the mixture 5opening valve for said air inlet opening, outlet. whereby the primarymixture Will be distributed radially over the face of said disk WILL E.DEWEY.

